Update LDAP authority and role handling to use LdapClient

[fer-marino]

refer #17028
Still a work in progress.

Replaced SpringSecurityLdapTemplate with LdapClient for improved LDAP search and entry handling. Refactored related methods and tests to handle NamingException, use LdapName for DNs, and support updated attribute handling with Attributes. Updated authority mapping logic to streamline nested group resolution and enhance test cases.

Integrarion tests for the NestedLdapAuthoritiesPopulator are failing. I can't find an efficient way to get the DN of the result set to build LdapAuthorities, so the resulting set is messed up.

Another major difference with the LdapTemplate is that every search result contains at least the key spring.security.ldap.dn while the LdapClient does not. This breaks some other tests that maybe can be removed.

Another note worth mentioning is that integration tests still uses ApacheDSContainer, which is deprecated and should be replaced by UnboundIdContainer

Comments are very welcome! :)

[jzheaux]

Thanks for the contribution, @fer-marino. It think there may be some misunderstanding that is causing this extra work for you. We cannot change public or protected constructors or methods as this will break applications when they upgrade. For this reason, the ticket indicates the following (emphasis mine)

Add an LdapAuthoritiesPopulator implementation that uses LdapClient

I hope this helps with some of your concerns about failing tests, etc., as well.